Dispelling Myths and
Misconceptions Through the
Visualization of Quantum
Concepts in General Chemistry
Morton Hoffman,1 Dan Dill,1
Peter Garik,2 Alex Golger1
1) Department of Chemistry
2) School of Education
Boston, Massachusetts 02215
QC in some current general
Zumdahl, ÒChemical Principles,Ó3rd Ed. (1998): Chap. 12
Hill and Petrucci, ÒGeneral Chemistry,Ó2nd Ed. (1999): Chap. 7 & 8
Moore, Stanitski, and Jurs, ÒChemistry: The Molecular Science,Ó(2002): Chap. 7
Brady and Senese, ÒChemistry: Matter and Its Changes,Ó 4 Ed. (2004): Chap. 8
Zumdahl and Zumdahl, ÒChemistry,Ó5th Ed. (2000): Chap. 7
McMurray and Fay, ÒChemistry,Ó4th Ed. (2004): Chap. 5
Atkins and Jones, ÒChemical Principles,Ó3rd Ed. (2005): Chap. 1
Petrucci and Harwood, ÒGeneral Chemistry,Ó7th Ed. (1997): Chap. 9
Brown, et al., ÒChemistry: The Central Science,Ó10th Ed. (2006): Chap. 6
ACS, ÒChemistry,Ó(2005): Chap. 4
What topics are presented?
What attitudes toward QC do
students bring into general
Fear and loathing from pre-college science
courses and the popular culture.
Rumors that it’s about some strange
equations and dead, Germanic guys with
umlauts in their names.
Concerns that it’s about “mechanics” and
other non-inspiring subjects from physics.
Do students “get it?”
Most are puzzled about the whole thing.
Many see it merely as impenetrable mathematics
with no relevance to reality.
Some can do the algorithmic “plug-and-chug”
calculations without too much difficulty.
A few have a satisfactory conceptual
A couple are inspired by it and want to learn
Why should we bother with
It is basis for understanding spectroscopy,
electronic structure, periodic properties.
It is the essence of nanotechnology,
quantum computing . . . the future.
It provides insight into the deeply
microscopic (atomic, molecular) world.
It encompasses all of chemistry and is
General chemistry students
and Quantum Concepts
Quantum Concepts are among the most
challenging and unsatisfying topics for students
The quantum world makes no sense to everyday
intuition; at best, it’s all mathematics.
Failure to reconcile this intuition with quantum
behavior results in deeply seated myths and
Quantum Concepts do not seem to provide useful
insights for the rest of general chemistry.
An e-mail from a chemistry
professor at a four-year college
I certainly find that chapter (Chapter 6, in Brown and
LeMay I think) the hardest to teach...because, of
course, it's such a skimmed-over thing, without the
required mathematics. And then we just “pull out of the
hat” things like orbitals and quantum numbers. Once
we get into trends and hybridization, things settle down
again, but I certainly sense general revolt for a week or
What are some of the prevalent
myths and misconceptions
about Quantum Concepts?
The electron “waves” as it moves.
Through the absorption or emission of
light energy, electrons “jump” from one
quantum level to another.
Electrons “go around” the atom in a
particular quantum state.
Spectral lines represent “energy levels”
of the electron.
More myths and
When a “photon” is absorbed, light
vanishes; when a “photon” is emitted,
The “orbital” pictures represent the
regions in space in which the electrons
The “wavefunction” is a static
mathematical representation of the
electron in the atom.
These myths and
time has been left out!
and avoid missed
Incoming general chemistry
students and physics
They have a good understanding of the spatial
description of waves (wavelength and amplitude).
They have a poor understanding of the temporal
description of waves (period and frequency).
They have difficulty linking the spatial and temporal
behavior of waves.
They are weak in their understanding of the
energetics of waves and the nature of fields.
They generally do not know that EM waves have
electric and magnetic fields associated with them.
Learning cycle-based activities: data collection,
Interactive guided-inquiry software that examines
spectroscopy and electron orbital energies.
Interactive graphical renderings of time-dependent
atomic orbitals without mathematics!
Visualizations of the beats that correspond to
dipole excitations of atoms.
A visual introduction to the selection rules for
quantum absorption and emission.
Guided inquiry software
Used in conjunction with lecture demonstrations,
lecture/discussion workshops, lab exercises, and
Project 1: spectroscopy of atomic hydrogen and
Project 2: introduction to the normal modes of one-
(cable) and two-dimensional (square and circular
membranes) waves with analogy to the modes of a
Project 3: time-dependent behavior of electron orbitals
and their interaction with light.
The Resolution: Include Time!
When time is properly included, three
key concepts emerge:
The electron wavefunction does change
Electron density in a specific energy state
is nevertheless static: nothing moves,
nothing evolves, nothing changes.
The mixing of energy states accounts for
all motion, evolution, and change.
Our Conclusion: Include
Proper treatment of “time” in quantum
systems is crucial.
It provides the correct framework on which
students can reason about quantum
Without this framework, myths and
misconceptions are the inevitable
Why should students in general
chemistry learn this stuff?
Nature continually undergoes change.
Chemistry is the science of change.
Time dependence in the quantum world is
the analogue for all change in chemistry.
Quantum time dependence is the basis for
students to learn how and why things
Peter Carr, Programmer
Joshua Csehak and Lars Travers, Ace Coders
Judith Kelley, Project Evaluator
Funding, U.S. Department of Education Fund
for the Improvement of Post Secondary
Education (FIPSE Grant P116B020856)